Doses of vaccines rejected as countries fine-tune their inoculation campaigns will go to poor countries where possible to counter a "shocking imbalance" in distribution, international health officials said on Friday.

Australia and the Philippines limited use of AstraZeneca's COVID-19 vaccine on Thursday, while the African Union dropped plans to buy the shot amid global shortages, dealing further blows to the company's hopes to deliver a vaccine for the world.

More than 700 million jabs have been administered worldwide against the disease, but 87% have gone to high income or upper middle-income countries, with low income countries receiving just 0.2%, Tedros Adhanom Ghebreyesus said

Geneva (AFP) - Covax backed the AstraZeneca jab on Thursday as the scheme celebrated shipping coronavirus vaccine doses to 100 different territories around the world, despite delays dogging deliveries.

There is a "shocking imbalance" in the distribution of COVID-19 vaccines worldwide and most countries do not have anywhere near enough shots to cover health workers and others at high-risk, WHO Director-General Tedros Adhanom Ghebreyesus said on Friday.

The COVAX vaccine facility has delivered nearly 38.4 million doses of COVID-19 vaccines to 102 countries and economies across six continents, six weeks after it began to roll out supplies, according to a statement on Thursday.